On Fri, 16 Mar 2012, Bjørn Mork wrote:
Shannon Dealy <de...@deatech.com> writes:
I created a file "/etc/modprobe.d/iwlagn.conf" and placed the
following line in it:
options iwlagn 11n_disable=1 11n_disable50=1
Note that the 11n_disable50 options was removed in 3.0 and the iwlagn
module was renamed to iwlwifi in 3.2.
Unfortunate, since further testing shows that it is the 11n_disable50=1
that matters. Disabling either of the above options makes my link stable,
and since 11n_disable=1 would effectively cause "11n_disable50" to happen
as well, the implication is that the problem is in the code which is/was
controlled by the 11n_disable50.
Would be nice if anyone can confirm if this fixes the deep sleep problem
as well.
Which makes this workaround pretty much irrelevant to any current Debian
kernel as noone(?) has seen the bug in 2.6.32.
While it may not be relevant to you, it is completely relevant in that it:
- provides developers with a narrowed range of places to look for the problem
in all versions of the kernel/driver code, including those were the
option was removed (they can easily check what part of the code it
previously disabled)
- using just the 11n_disable option should still solve the stability
problems I am seeing and possibly the deep sleep as well (need
confirmation on that) for people running 3.x (though granted it is not
a great workaround given the performance hit)
- I assume you are speaking with regard to 2.6.32 being the default
stable kernel so it won't affect people running stock Debian stable?
I don't recall seeing confirmation from anyone that the problem went
away by downgrading to 2.6.32.
Are you still using the 2.6.39-1 kernel you originally opened this bug
against?
[snip]
Yes, though it has been rebuilt for debug tracing of the iwlagn driver.
Unfortunately I can't afford the down time right now that a kernel
upgrade beyond 2.6.39 would entail (other software would have to be
upgraded and that might require that I write some code as well to
deal with the kernel changes). I also can't downgrade to 2.6.32
(assuming that it would make any difference) as it doesn't support some of
my hardware.
FWIW
Shannon C. Dealy | DeaTech Research Inc.
de...@deatech.com | - Custom Software Development -
Phone: (800) 467-5820 | - Natural Building Instruction -
or: (541) 929-4089 | www.deatech.com